Soil salinity is a growing threat to agricultural sustainability, particularly in arid and semi-arid regions. Understanding how salinity affects soil organic matter (OM) is critical for improving land management and maintaining soil health. This study addresses these challenges by exploring the molecular-level impact of salinity on OM dynamics. Salinity exerts a depth-dependent influence on lignin and microbial lipid biomarkers, which are used to trace plant inputs and microbial activity, respectively. For lignin biomarkers, in the surface layer (0–20 cm), higher salinity levels are associated with increased Syringyl/Vanillyl (S/V) and Cinnamyl/Vanillyl (C/V) ratios, suggesting enhanced preservation of syringyl (S) and cinnamyl (C) units. In the middle layer (−20 to −60 cm), higher salinity correlates with elevated SVC (total lignin phenols), Acid/aldehyde (Ad/Al) ratios, and other markers of selective lignin degradation. For lipid biomarkers, salinity modulates microbial adaptation and turnover, as seen in variations in i17 (iso-C17), a17 (anteiso-C17), and unsaturation indices such as C16:1/C16, reflecting Gram-positive and Gram-negative bacterial activity. These trends indicate that salinity stress alters microbial lipid profiles, leading to reduced turnover and enhanced preservation in deeper, more anoxic environments. Principal Component Analysis (PCA) revealed depth- and salinity-driven patterns that distinguish between surface microbial transformations and deep-layer molecular preservation. Correlation analysis of Principal Components (PCs) with salinity revealed that higher salinity favored molecular stability in deeper layers, while lower salinity was associated with microbial transformations in surface layers. These findings underscore salinity’s critical role in OM stabilization and turnover, and provide a molecular framework to guide sustainable management of saline soils.

The demand for sustainable energy storage solutions has led to increased interest in biomass-derived carbon aerogels as electrode materials for supercapacitors. These materials offer a high surface area, tunable porosity, and excellent electrochemical properties while utilizing renewable and waste biomass sources. This study evaluates the electrochemical performance of various biomass-based carbon aerogels, including those derived from cellulose, lignin, chitosan, and biomass waste, to identify key factors influencing supercapacitor efficiency. Principal Component Analysis (PCA) is employed to systematically analyze the relationships between structural and electrochemical properties, such as the specific surface area, specific capacitance, capacity retention, rate capability, energy density, and power density. The PCA results indicate that the first two principal components (PC1 and PC2) explain 58.20% of the total variance, with capacity retention (26.22%), energy density (19.55%), and specific capacitance (18.48%) identified as the most critical quantitative factors influencing supercapacitor performance. Chitosan-derived carbon aerogels exhibit superior capacitance and energy density, with a specific capacitance reaching up to 1074 F/g and energy density of 40.18 Wh/kg, whereas lignin-based aerogels demonstrate a high structural stability and capacity retention (up to 97.4%). Biomass waste-derived aerogels, despite their lower performance (176–298.6 F/g capacitance, 81.6–91.7% retention), provide cost-effective and environmentally sustainable alternatives. This quantitative analysis offers valuable insights into the rational design of high-performance, biomass-based aerogels, contributing significantly to the development of sustainable energy storage technologies.

In this study, we used Principal Component Analysis (PCA) to evaluate the physical and operational properties of palladium (Pd)-based membrane composites, focusing on variables like temperature, differential pressure (ΔP), thickness, hydrogen (H₂) permeability, and H₂ flux. The analysis revealed that the first two principal components explained 53.16% of the total variance, indicating moderate explanatory power. Interdependencies were observed among temperature, thickness, H₂ flux, and H₂ permeability, while ΔP functioned independently. This study found similarities among membranes, such as eco-friendly chitosan-based membranes, which performed comparably to conventional options like Pd–PSS and Pd–Cu/αAl₂O₃. Overall, PCA proved to be an invaluable tool for uncovering hidden patterns, optimizing experimental processes, and deepening the understanding of Pd-based membranes. The findings underscore PCA’s potential to enhance material performance and promote sustainable alternatives, with practical benefits for advancing hydrogen separation technologies. This study illustrates how data-driven approaches can refine material analysis and drive innovation in membrane design.

Background: Cement production is a significant source of global CO ₂ emissions, driving the need for sustainable alternatives in construction. Ground granulated blast-furnace slag (GGBS) has emerged as a promising supplementary cementitious material; however, its performance across wide replacement ranges and its combined environmental and economic implications remain insufficiently characterised, particularly in hot and arid climatic contexts such as the Gulf region. Methods: Nine mortar mixes incorporating GGBS as a partial replacement for ordinary Portland cement (OPC) were prepared at replacement levels ranging from 5% to 100%. Compressive and flexural strength were assessed at 7, 14, and 28 days of curing. Life cycle assessment (LCA) and life cycle cost (LCC) analyses were conducted to evaluate the environmental and economic performance of each mix over its service life. Results: Replacement levels between 20% and 30% yielded optimal compressive strength, surpassing the OPC control at 28 days. Higher replacement levels enhanced flexural strength, though the highest recorded values require further validation. LCA results confirmed a progressive reduction in CO ₂ emissions with increasing GGBS content, while LCC analysis demonstrated improved cost efficiency relative to the OPC reference. Discussion: A 30% GGBS replacement level is identified as the optimal balance between mechanical performance, environmental benefit, and economic efficiency. These findings support the adoption of GGBS-blended mortars as viable, sustainable alternatives to conventional OPC-based construction materials in the Gulf region and comparable climatic environments.